Warning signal switch



March 11, 1958 s. c. WURM 2,826,655

wARNNG SIGNAL SWITCH Filed oct. 8, 1956 INVENTOR.

@74A/Ey C. WMP/14 United States Patent O1 WARNING SIGNAL SWITCH Stanley C. Wurm; Detroit, Mich. Application October 8, 195 6', SerialNo'. 614,613

This invention relates to electrical switches.' and refers more particularlyv to a warning signal switch.

One object of this invention is to provide a switch for closing an electrical circuit whenever the switch unitA or its mounting is disturbed. The switch is designed particularly for use with'an alarm used in connectionwith an. automobile to prevent its theft. The switch isA such that thel slightest movement of the automobile is sufiicientto disturb the switch or its mountingl to the degree necessary to close the switch and therebyenergize'the alarm.

Another object. is to provide a warning'signalswitchv low casing 12 which is formed of a suitable transparent.

dielectric material such as Lucite. The casing. 12 has a cylindrical sidewall 14 and the ends are closed by caps' 16. A pair of terminals 18 and 20 are provided; The terminal 18 has an enlarged pendulum supporting portion' 22 within the casing adjacent the upper end, and a reduced. portion 24 integral with the portion.22 extends through a suitable opening 26 in the side wall of the casing. A pair of nuts 28 are threaded on the. reduced outer end portion 24 of the terminal 18 to lockit in place on the casing.

The other terminal 20 has a ring'supporting portion 32 within the casing and a reducedportion 34.extend ing through a suitable opening 36 in the side wall" of the casing. A pair of nuts'38 are threaded on the reduced portion of the terminal 20 to secure it in place ony the casing.

The terminals 18y and 20 are carried by the casing in verticallyy spaced relationship to each other and these terminals are of course formed of a suitable electrically conductive material.

The upper terminal 18 has a cup-shaped recess 40 in the upper side of the pendulum supporting portion 22, and a passage 42 in the bottom of the portion 22 connects intothe bottom of recess 40. An elongated pendulum 44, of suitable electrically conductive material, extends into the recess 40 through passage 42. The

upper end of the rod is enlarged as indicated at'48, andi the enlarged portion is of greater diameter than the passage 42 but of less diameter than the recess 40 so that the pendulum is loosely supported by the upper'terminal 18.

A ring 50 of suitable electricallyv conductive material' 2,826,655 Patented Mar. 11, 1958 rice is secured4 to' the-portion 32 To'terrninal 20 `and loosely surrounds the lower end portion of the pendulum 44. The passage 42inv the upperY terminal is of a diameter sufficiently greater than thatoffthe'pendulum to permit thependulum tozswing Vin any direction into engagement with the ring 50:

A bushing 52 is" carried by the bottom cap of the. casing. Thisbushing has arr annularflange 54 adjacent the upperaend'within the casing, andI the relativelyV reduced `portion 56 Vextends'downwardly through a suitable openinginthe bottomgcap ofthe casing. A nut 60 is threaded on the'lower end portion of' the bushing; andv a fiber washer 61 isA sleeved'overV the external portion of the bushing between the-bottom' ofthe casing andithe nut. Thel bushing'is'tig'htly'secured to the casing by drawing the nut up tight.`

Thebushing has, athrough passage 62V extending from the upper` end to'thelower end,. and a clamp 64 of Bakelite or' similar dielectric material has a stem part 66"which projects through the. passage 62 in the bushing and beyond'the lower end thereof. The stem part 66 has an upper cylindrical portion 68 which has a close sliding tin the-V upper cylindrical portion of the passage 62, and the lower end portion 70 of the stem part isA cylindrical and has a close sliding fit inthe lower reduced cylindrical portion 72. of the passage 62'. A compression coil spring' 74.surrounds the lower portion 70 of the stern part 66 in the annular space between the stem part'andthe bushing. The upper end of the spring bears against the shoulder. between the enlarged upper portion and thereducedl lower portion of the stem part andy the lower end'of the spring bears against the shoulder between the enlarged upper portion andthe reduced lower portion of the passage 62.' The spring thus normallyy urges theclamp upwardly to the position illustrated in Fig.` 2.

The clamp has a head portion. at the upperend of the stem part and the upper surface 82 of the head portion isl concave as illustrated. In the Fig. 2 position of the clamp, the upper surface 82'thereof bears against the ball 84 threaded on the lower end of the pendulum 44 to urge thependulum upwardly. The inner end of the pendulum supporting part 22 of the upper terminal 18 is peened over as indicated at 86 after assembly of the pendulum with the upper terminal to conne the upper end of the pendulum4 to the recess 40 when. the pendulum is urged upwardly by the clamp. In this position of the pendulum, with its lower endY engaged by the clamp and its upper end bearingagainst the peenedover portion, the pendulum cannot swing.l

An operating lever is carried by the lower end portion of the stempart. The lever 90 is generally T-shaped having a gripping stem 92 and a head. 94. extending transversely of the. gripping stem at one end thereof. The head 94 is formed with a channel or recess 96 along the top edge thereof extendingfrom one side of the head to the other. The recess 96 is sufficiently wide to receive the lower end of the stem part, and a pin 98 extending through the head across the recess pivotally connects the lever 90 to the stern part. When the lever is in the generally upright position of Fig. 2, the clamp is free to move upwardly by spring 74 to lockthe pendulum against swinging. However, the lever may be turned ninety degrees in either direction to the position of Fig. lin which one end of the head will bear against the lower endof the bushing 52 and retract the clamp to the Fig. l position in which it is withdrawn to a position beneath the pendulum and wherein the enlarged upper end of the pendulum is supportedby the base of the recess 40 to enable it to swing freely. The upper end of the head 94 of the lever is rounded atthe opposite ends as shown at 100 so that the head will haveV a-ca'nlming` action against 3 the bushing as the lever is swung to the Fig. 1 position. Thus it is not necessary to withdraw the clamp with a downward pull, the camming action making it possible to retract the clamp by merely .rotating the lever to the Fig. l position.

The casing has an opening 101 in its cylindrical side wall, and apertured plates 102 and 104 are secured to the inner and outer sides of the cylindrical side Wall of t the casing with their apertures registering with the opening 101. A mounting 106 is provided including an arm 108 having a ball 110 on the outer end, the bail being received within the registering apertures in the plates 102 and 104 and the opening 101. The apertures in the plates are of somewhat smaller diameter than the ball so that the portions of the plates dening these apertures bear against opposite sides of the ball. Since the plates are resilient, they frictionally engage the ball as illustrated in Fig. 3 so as to retain the casing in any desired position of adjustment or setting with respect to the ball. The arm 103 is connected to an arm 112 by a coupling 114, and a suction cup 116 is secured to the outer end of arm 112. The suction cup may be mounted on the instrument panel A of an automobile, for example, or on any other part of the vehicle. Obviously the switch may also be attached to any vehicle or other Vdevicewhich is desired to be protected. Thus it may be attached to a fixed wall, for example, in position to be engaged by a door or window when opened, thereby protecting against unauthorized entry. Y

In use, the switch will be connected in the circuit of an alarm such as the audible signal device 120. The leads 122 and 124 of the circuit are respectively connected to the terminals 18 and 2t? through battery B, and a manual switch 126 is provided in the circuit.

in use, the switch will be attached to any portion of the vehicle such as the instrument panel A. Preferably the switch will be located in a concealed area. The casing will then be oriented with respect to the swivel connecticn provided by the ball 110 so that the pendulum hangs freely and does not contact any portion of the ring 50, the clamp 64 of course being retracted during this adjustment. Assuming that the switch 126 is closed and the clamp retracted, the vehicle may now be left unattended, and is completely protected against theft. Any slight disturbance of the vehicle, as might be occasioned by a person entering the vehicle, will cause. the pendulum to swing into at least momentary Contact with the ring to complete the circuit to the alarm 120 energizing the latter to produce an audible alarm or signal.

When not in use, the switch may be rendered inoperative by swinging the lever 90 to the Fig. 2 position in which the pendulum is clamped against swinging. Also, the switch 126 may be opened.

It will be understood that the ball at the lower end of the pendulum is secured thereto, as by a threaded connection, after the pendulum has been assembled with the upper terminal.

The coupling 114 enables replacing the rod 112 and suction cup with another type of mounting, such as a mounting plate or bracket.

The clamp 64 not only prevents the circuit from being closed by movement of the casing, but it also prevents the pendulum from swinging when the switch is not in use. The switch 126, while it opens the circuit, obviously will not prevent the pendulum from swinging. Needless swinging of the pendulum would result in excessive wear.

What I claim as my invention is:

l. An electrical switch comprising a casing, a irst electrical terminal carried by said casing with a portion exteriorly of said casing for connection in an electrical circuit and a portion interiorly of said casing, a pendulum of electrically conductive material within said casing, the upper end of said pendulum being swivelly connected to said interior portion of said terminal and depending therevfrom, a second electrical terminal carried by said casing d beneath said rst terminal and having a portion exteriorly of said casing for connection in the electrical circuit and a portion interiorly of said casing including a ring of electrically conductive material loosely encircling the lower end portion of said pendulum, said pendulum being adapted to contact said ring to complete the circuit between said terminals upon swinging of said pendulum as when said casing is disturbed, means for mounting said casing in a position in which said pendulum hangs freely within said ring and out of contact therewith, a clamp carried by said casing for movement from a lower inoperative position to an upper operative position engaging thev lower end of said pendulum and holding it in a position out of contact with said ring, an actuating lever for said clamp pivoted thereto for swinging movement from an inoperative position to an operative position, said lever having a cam portion engageable with a portion of said casing upon movement of said lever to operative position eiective to withdraw said clamp to inoperative position, and spring means for moving said clamp to operative position in the inoperative position of said lever.

2. An electrical switch comprising a support, a first electrical terminal carried by said support, a pendulum of electrically conductive material swivelly supported by said terminal. and depending therefrom,fa second electrical terminal carried by said support including a ring of electrically conductive material spaced beneath said lirst terminal and loosely encircling said pendulum, said pendulum being adapted to contact said ring to complete a circuit between said terminals upon swinging of said pendulurnas when said support is disturbed and a releasable clamp carried by said support for movement from an inoperative position to an operative position holding said pendulum out of contact with said ring, an actuating lever for said clamp pivoted thereto for swinging movement from an inoperative position to an operative position, said lever having a cam portion engageable with a portion of said support upon movement of said lever to operative position effective to move said clamp to inoperative position, and spring means for moving said clamp to operative position in the inoperative position of said lever.

3. An electrical switch comprising a support, a rst electrical terminal carried by said support, a pendulum of electrically conductive material swivelly supported by said terminal and depending therefrom, a second electrical terminal carried by said support including a ring of electrically conductive material spaced beneath said first terminal and loosely encircling said pendulum, said pendulum being adapted to contact said ring to complete a circuit between said terminals upon swinging of said pendulum as when said support is disturbed, a releasable member supported for movement from an inoperative position to an operative position holding said pendulum out of contact with said ring, means for moving said member to its operative and inoperative positions including an actuating lever pivoted to said member for swinging movement from an operative to an inoperative position, an abutment, said lever having a cam portion engageable with said abutment upon movement of said lever to operative position eective to move said member to inoperative position.

4. The structure set forth in claim 3 including resilient means normally urging said member to operative position.

5. An electrical switch comprising a support, a rst electrical terminal carried by said support, a pendulum of electrically conductive material swivelly supported by said terminal and depending therefrom, a second electrical terminal carried by said support including a ring of electrically conductive material spaced beneath said first terminal and loosely encircling said pendulum, said pendulum being adapted to contact said ring to complete a circuit between said terminals upon swinging of said pendulum as when said support is disturbed, a releasable member supported for movement from an inoperative position to an operative position holding said pendulum out of contact with said ring, means for moving said member to its operative `and inoperative positions including a camming element engageable with said member and selectively operable to move said member to inoperative position.

6. An electrical switch comprising a support, a first electrical terminal carried by said support, a pendulum of electrically conductive material swivelly supported by said terminal and depending therefrom, a second electrical terminal carried by said support including a ring of electrically conductive material spaced beneath said first terminal and loosely encircling said pendulum, said pendulum being adapted to contact said ring to complete a circuit between said terminals upon swinging of said pendulum as when said support is disturbed, a releasable member supported for movement from an inoperative References Cited in the le of this patent UNITED STATES PATENTS 1,651,919 Douglas Dec. 6, 1927 1,891,993 Larson Dec. 27, 1932 2,068,339 Logan Ian. 19, 1937 2,075,040 Kieber Mar. 30, 1937 2,334,316 Cloud 1 Nov. 16, 1943 2,369,977 OToole Feb. 20, 1945 

